Knicks president Donnie Walsh said he could be amenable to a Nate Robinson buyout if the number was right.

Walsh and Robinson’s agent Aaron Goodwin spoke yesterday about the Saturday-night trade demand and will have ongoing dialogue to resolve “Nate-Gate.”

Walsh has acknowledged trading Robinson could be difficult because he’s only willing to accept an expiring contract in return.

The other roadblock is cap mathematics, as Robinson is a “base-year compensation” player, meaning despite his $4 million contract, the Knicks can only accept back a player whose contract is $2.6 million. If both teams are over the cap, a deal is not possible because the salaries must match. A third team would have to be involved.

When asked directly if he’d be willing to buy Robinson out like he did banished Stephon Marbury last February, Walsh did not dismiss the idea.

“When I signed him I thought he’d be an important player on the team,” Walsh said. “I don’t know. We’ll have to talk about it, OK, what is it [the number].”

If the Knicks can save $1 million on his base contract of $4 million, both sides could be willing to go for it. That could mean a net savings of $2 million since Robinson is owed a $1 million bonus if the Knicks make the playoffs. Incredibly, with their Nate-free surge, the Knicks (10-17) are just one game behind eighth-place Detroit. The top eight teams make the playoffs.

Goodwin, in a text message, said yesterday: “We spoke and will continue to speak on it.”

Walsh said he hadn’t heard from any teams inquiring about Robinson since reports surfaced Saturday night that Goodwin had requested a trade. There’s a chance Goodwin has been allowed to talk to other clubs on Robinson’s behalf, though Walsh said last night he had “no updates.”

There are teams who’ve had interest in Robinson, including Orlando, Sacramento and the Lakers. The Bulls, whom the Knicks host tonight (7:30, MSG, ESPN 1050 AM), are looking for scoring and Cleveland’s LeBron James has spoken glowingly about the 5-foot-7½ sparkplug.

Walsh said because the Knicks are 6-3 since Robinson’s been banished from the rotation, nothing is changing.

“All I make of it is this rotation is working,” Walsh said. “And there’s a reason not to break it up right now, which has nothing to do with Nate. If you’re not playing when the rotation is working, something is going to have to happen before I get a chance to play. That’s common sense.”

Robinson has tried to stay above the fray, saying Sunday he hopes to “stay a Knick.” Walsh admitted to being confused, saying Robinson stated “the opposite” of Goodwin’s sentiment.

Yesterday, Robinson spent 40 minutes playing 1-on-1 with assistant coach Herb Williams’ teenaged son, Jabrille, after practice, seemingly in good holiday spirit. When he left the court, Robinson said: “I’ve said everything I had to say [on Sunday].”

Coach Mike D’Antoni seems unfazed by “Nate-Gate.” His mood has lifted since the team has started winning. D’Antoni has looked like a genius for making the controversial move to bench his third-best scorer.

“Nate’s been great,” D’Antoni said. “Aaron has to do what’s good for Nate as his client. I have to do what’s good for the Knicks. Sometimes they don’t always have the same agenda. Sometimes you have to have patience and things work out. Sometimes they don’t work out.”

⇒Larry Hughes, whose missed last three games with sprained left groin, is expected back tonight.